Off-road vehicles can include control systems for controlling a plurality of outputs in response to command signals. For example, an off-road vehicle may include systems for controlling a four-wheel drive (4WD) clutch, a differential lock (DL), a power take-off (PTO) clutch, an engine speed actuator, and a transmission. Specific off-road vehicles may include control systems for other outputs. Agricultural tractors, for example, may include control systems for raising and lowering mounted, semi-mounted and trailing implements (e.g., drills, planters, plows, drags, fertilizer spreaders, etc.), and control systems for applying farming inputs using the implements. Mounted implements are coupled to tractors by hitch assemblies (e.g., three-point hitches), and trailing implements are coupled by drawbars. Combines include systems for controlling settings of crop processors such as headers, rotors, concaves, sieves and cleaning fans. Construction vehicles include systems for controlling the settings of construction equipment devices such as booms, arms, buckets and augers.
The command signals applied to off-road vehicle control systems are typically generated by operator-actuatable command devices. Command devices may include discrete (e.g., switches or pulsers) and analog devices (e.g., levers or potentiometers). For example, a DL may be locked, or a 4WD or PTO clutch engaged, based upon actuations of a switch. An engine speed actuator may be controlled based upon positions of a throttle lever. A transmission gear may be selected based upon positions of a shift or pulser lever. An implement may be raised and lowered based upon positions of a position or draft force lever or actuations of a raise/lower switch. A farming input may be applied by an implement based upon settings of a lever which controls a hydraulic valve supplying hydraulic fluid to an actuator on the implement. The command signals on combines and construction vehicles also depend upon command devices. The command signals generated by the command devices may control the outputs directly, or may be combined with other signals by a control circuit and then used to control the output.
Modern off-road vehicles are being equipped with a plurality of control systems for controlling many outputs with increased levels of control. This trend is likely to continue or accelerate with the growing use of digital control systems and data busses. To provide effective control over the increasing numbers of more complex control systems, the cabs of off-road vehicles are being equipped with more operator-actuatable command devices requiring more sequential or concurrent actuations.
The situation wherein a tractor exits a field at the headlands illustrates the many command device actuations required for effective control. For example, it may be desired to perform the following output functions each time a tractor exits a field: raise hitch; disengage 4WD; unlock DL; disengage PTO; lower throttle setting; and shift transmission. Each step may require actuation of a separate command device. The sequence is reversed as the tractor re-enters the field. The sequences repeat each time the tractor exits and re-enters a field. A tractor performs other sequences in other situations, and other types of off-road vehicles perform other sequences.
For effective control, each command sequence step may need to be performed based upon a different event. For example, the operator may have raised the hitch when the tractor was a certain distance from the border of a field, disengaged 4WD after the hitch reached a transport position, unlocked DL one second after starting to raise the hitch, disengaged PTO at the field border, lowered the throttle setting while the implement was raised, and shifted the transmission two, three and four seconds after starting to raise the implement. The operator may have sensed the occurrence of each event and actuated each command device appropriately. Thus, each step may occur in response to an event based upon a geographic position, feedback signal, timer value or other signal.
As the example shows, each command sequence may require actuation of a number of command devices, with each command device actuated once or more than once. Further, effective control may only occur if the correct command devices are actuated in the correct sequence in response to the correct events. Thus, effective control may require a high level of operator skill, training and experience. However, even a skillful operator may not achieve optimal efficiency due to fatigue caused by the high workload needed for effective control. Thus, the efficiencies achievable by off-road vehicles equipped with modern control systems may not be realized due to imprecise command device actuations caused by inadequate operator skill, training or experience, or by fatigue.
Accordingly, it would be advantageous to provide an improved system for controlling outputs associated with off-road vehicles. It would be advantageous to provide a control system for an off-road vehicle which can record a command sequence, and then repeat the recorded sequence. Such a control system could control multiple outputs with each output receiving one or more commands. It would be advantageous to provide a control system for an off-road vehicle which can repeat a plurality of command sequences in response to separate playback signals having either manual or automatic triggers (e.g., geographic position). It would be advantageous if the command sequences could be erased, viewed and edited. Further, it would be advantageous to provide a control system for an off-road vehicle which can repeat a command sequence wherein the steps occur in response to events based upon a geographic position, a feedback signal, a timer value or another signal. It would further be advantageous to download and upload command sequences to external devices.